1. Field of the Invention
The present invention relates to the field of trailer hitch attachments, and more particularly, to a trailer hitch attachment system with multiple receivers that may be assembled in a variety of configurations and that may accept a wide variety of hitch-mountable devices.
2. Description of the Related Art
A need exists to be able to transport items on the exterior of vehicles, and numerous products are available that provide storage devices (such as cargo carriers and bicycle racks) that may be removably attached to a vehicle's trailer hitch receiver. These products are commonly used to transport bulky or dirty items, such as folding tables and chairs, barbeque grills, portable generators, firewood and other items that are used for camping, hunting, field work, etc. In many cases, it would be advantageous to carry more items than are currently practical to carry with existing carrier products.
The present invention presents a solution to the problem of insufficient carrying capacity by providing multiple trailer hitch receivers that may be connected together at variable spacings and configurations so that multiple carriers may be installed on a vehicle simultaneously. For example, the present invention may used to simultaneously support a firewood carrier, a food cooler carrier, a camping gear carrier and a bicycle rack. Although there are numerous carrier products that are the subject of existing patents or patent applications, and also numerous unpatented products on the market, none of these devices is similar to the present invention in terms of structure or function.
U.S. Pat. No. 5,511,831 (Kravitz, 1996) discloses an adjustable-width trailer hitch assembly that may be attached to the frame of a wide variety of vehicles. This invention comprises an adjustable-width frame mounting assembly and a single hitch receiver. The invention does not provide for multiple receivers.
U.S. Pat. No. 6,460,745 (Weaver, 2002) discloses a trailer-hitch mounted bicycle rack that provides for a bicycle to be carried with the frame of the bicycle oriented parallel to the long axis of the vehicle. The invention also provides a swivel mechanism so that the bicycle may be temporarily rotated downward to open the trunk of a vehicle. The invention does not provide for multiple receivers.
U.S. Pat. No. 6,662,983 (Lane et al., 2003) discloses a trailer-hitch mounted rack system that is described as “multi-configuration, multi-purpose.” The invention comprises extension legs, a crossbar with extension arms and a folding cargo platform. The various components of the system may be assembled in a variety of configurations to optimize the system for carrying a particular type of cargo; for example, one assembly configuration may be used for carrying a bicycle and another assembly configuration for carrying sheets of building material. The screw-type connectors of the invention are claimed to eliminate wobble between the connected parts. There is no provision in the invention for attaching multiple receivers or for attaching additional trailer hitch-compatible accessories.
U.S. Pat. No. 6,695,184 (Higginbotham III, 2004) discloses a trailer hitch-mounted bicycle carrier that carries a single bicycle vehicle in a transverse orientation. The invention comprises a mechanism that pushes downward on the seat of the bicycle, compressing the shock-absorber spring of the bicycle and thereby holding the bicycle firmly in place within the carrier with spring force. There is no provision for multiple receivers or for attaching other trailer hitch-compatible accessories.
U.S. Pat. No. 7,559,570 (Cearns, 2009) discloses a trailer hitch assembly with a vertically adjustable hitch ball. There is no provision for multiple receivers or for attaching other trailer-hitch compatible accessories.
U.S. Pat. No. 8,366,373 (Wood, 2013) discloses a collapsible mount that may be optionally attached to a trailer hitch and that is used to support a cargo-loading device such as a winch. The invention comprises horizontal and vertical arms that are adjustable in length. There is no provision for multiple receivers or for attaching other trailer hitch-compatible accessories.
U.S. Patent Application Pub. No. 2004/00200955 (Darby) is an adapter mechanism that allows the saddle of a kayak to be attached to the vertical bar of a commercial carrier device. This invention is slidably attached to the vertical square post of a commercial cargo carrier (such as the EXTEND-A-TRUCK II™ device manufactured by Darby Industries of Falls, Pa.) that is attached to the trailer hitch of a vehicle. The purpose of the invention is to provide a secure attachment of a round tube or rectangular bar comprising the saddle of a kayak to the vertical bar of the cargo carrier. There is no provision for multiple receivers or for attaching other trailer hitch-compatible accessories.
An example of a non-patented commercially available hitch receiver is the ULTRA-TOW™ dual hitch extension (Item No. 32799-1551) sold by Northern Tool+Equipment of Burnsville, Minn. This device attaches to the trailer hitch receiver of a vehicle and provides for the attachment of two trailer hitch-mountable accessories. The receivers of this device are stacked vertically and oriented longitudinally. Unlike the present invention, there is no provision for providing vertically oriented receivers, for having transversely-oriented receivers, or for attaching additional receivers with extension members.